The 2008 presidential campaign in the United States raised expectations that the election of the Democratic Party candidate Barack Obama would lead to substantive change in the direction and execution of U.S. foreign policy. This has proved not to be the case. In relation to Obama’s Latin American policy, it is possible to speak of an entrenchment rather than a revision of George W. Bush’s strategy and assumptions. Examination of the complex of historical and institutional factors that constrain changes in modes and mechanisms of U.S. engagement suggests that the sclerosis that has characterized Obama’s conduct of hemispheric relations will compound the challenges faced by the United States on issues such as drugs, poverty, and immigration while deepening U.S. isolation and ideological distance from Latin American countries. At a theoretical level, Obama’s policy linearity with Bush calls into question assumed distinctions between Democratic and Republican Party approaches while highlighting the limited space for policy reform in the U.S. political system.